@article {128, title = {Cell recognition by mucus secreted by urn cell of Sipunculus nudus}, journal = {Nature}, volume = {253}, year = {1975}, note = {@ URN CELLS OF S. NUDUS SECRETE MUCUS THAT IS STICKY FOR FOREIGN CELLS BUT NOT FOR AUTOLOGOUS CELLS. TRIED TO ALTER AUTOLOGOUS ERYTHROCYTES TO MAKE THEM {\textquoteright}FOREIGN{\textquoteright} TO URN MUCUS. URN CELLS ARE BICELLULAR ORGANELLES ABOUT 20UM IN DIAM, W VESICULAR ANTERIOR CELL AND A LOOSELY ATTACHED CILIATED MUCUS-SECRETORY CELL (FIG.1). LATTER ORIGINATES IN EPITHEL. LINING OF COELOM, DETACH \& SWIM PICKING UP FOREIGN W NORMAL STICKY TAILS. CAN PRODUCE LONG TAILS IF INVASION OF FOREIGN STUFF.}, pages = {634-635}, keywords = {mucus, s. nudus, urn cells}, author = {Bang, F. B. and Bang, B. G.} }